Sensing and control mechanism for label dispenser

ABSTRACT

A SENSING APPARATUS ADAPTED FOR USE IN CONTROLLING THE MOVEMENT OR DETERMINING THE POSITION OF A CARRIER WEB TO WHICH IS ATTACHED SPACED ARTICLES. THE SENSING DEVICE IS A ROTATABLE MEMBER ENGAGEABLE WITH SUCCESSIVE LEADING EDGES OF THE ARTICLES CAUSING ROTATION OF THE SAME AND ACTUATION, THROUGH A CAM ROTATED IN RESPONSE TO ROTATION OF THE SENSING DEVICE, AND MEANS FOR CONTROLLING THE MOVEMENT OR POSITION OF THE ARTICLES.

June 22, 1971 DICKERSQN 3,586,578

SENSING AND CONTROL MECHANISM FOR LABEL DISPENSER Filed March 10, 1969 aX I 25 c l- //9 1 I Il I i 5. qiginlh. 30 34 33 n 2 |/Z7 I 23 Z2 IINVEN'IUR. 7 ,50 7 ARTHUR C. D/CKEPSON 'l I, I J l I MMfiflifiM 6 F1023ATTORNEYS United States Patent 01 hce 3,586,578 Patented June 22., 19713,586,578 SENSING AND CONTROL MECHANISM FOR LABEL DISPENSER Arthur C.Dickerson, St. Paul, Minn., assignor to Minnesota Mining & ManufacturingCompany, St. Paul,

Minn.

Filed Mar. 10, 1969, Ser. No. 805,575 Int. Cl. B65h 25/04; B3211 31/18US. Cl. 156361 3 Claims ABSTRACT OF THE DISCLOSURE The present inventionrelates to an improvement in a sensing device and in one aspect to animproved and simplified device for sensing the position of advancinglabels adhered to a flexible backing or carrier relative to theseparating edge of a dispenser.

It is necessary in the application of pressure-sensitive adhesive labelscarried by a low-adhesion carrier web onto packages that the position ofthe labels on the web with respect to a separating edge be preciselycontrolled. If the position of the labels as they move toward theseparating edge is not regulated, placement of the labels will not bemade to the articles in an orderly fashion. Many attempts at theconstruction of a suitable sensing mechanism have been made and someelaborate and some rather sophisticated and sensitive devices haveresulted. In each instance, the more movable pieces, the more partsthere are to Wear and to need replacement, and the more sensitive thedevices are the more apt they are to malfunction. Thus, simplicity is anecessary element of a succesful labelsensing apparatus.

Some examples of the prior art label-sensing devices are shown in US.Pats. No. 2,987,591; 3,039,516; 3,240,- 652; and 3,405,021.

The label sensing apparatus of the present invention provides a verysimple and accurate mechanism for sensing the position of spacedarticles movable therepast on a flexible web.

The present invention provides a label sensing apparatus which'isadaptable for use with various sized labels transported by a flexiblelow-adhesion carrier web to an applicating station of a label dispensingapparatus.

The present invention provides a label sensing device which ischaracterized by simplicity and accuracy.

The sensing device of the present invention comprises a rotatable starwheel, a cam driven by the star wheel, a spring to control theincremental movement of the star Wheel, and means responsive to theincremental movement of the star wheel for carrying out a controlfunction such as the movement, position, separation etc. of thearticles. The device is positioned in an area along the path of acarrier web where the surface opposite the device is unsupported.

The present invention will be more fully understood and its advantagesappreciated after reading the following detailed description whichrefers to the accompanying drawing, wherein:

FIG. 1 is a side elevational view of a support arm of a dispenser havinga sensing device constructed in accordance with the present invention;

FIG. 2 is a fragmentary plan view, partly in section of the dispenserillustrated in FIG. 1;

FIG. 3 is another elevational view of the dispenser of FIG. 1 showingthe sensing device in another operative position; and

FIG. 4 is an elevational view of a modified dispenser having a sensingdevice constructed in accordance with the present invention.

Referring now to FIGS. 1 through 3, there is shown a flexible carrierstrip or web 6 having positioned thereon a series of articles in spacedrelation, which articles are, in the illustrated embodiment,pressure-sensitive adhesive labels 7 adhesively secured to alow-adhesion surface of said flexible web 6, forming a label tape. Theflexible web 6 and labels 7 are advanced from a supply (not shown) by aguide roller 9 toward the surface of a label guiding plate 10 having atone end a transversely extending sharp separator edge 11 around whichthe flexible carrier strip 6 is drawn. The carrier Web 6 is drawn aroundthe edge 11 by means of two cooperating rollers 14 and 15, one of whichis driven by a motor (not shown) and the other of which is urged intoengagement with the flexible web 6, pressing the same into firmfrictional contacting driving engagement with the driven roller.Actuation of the motor affords movement of the flexible carrier web 6.Above the surface of the plate 10 is disposed a bridge-like member 18extending transversely of the plate and adjustably supported from anangle bracket 19. The angle bracket 19 may be carried by the plate 10,which plate could take the form of a swingable arm, or carried by afixed support arm on the applicator or a pedestal positioned at thelabelling station. The mounting for the bracket can be adjustablepermitting its use with various thickness of the labels. A guide member20 formed of light flexible sheet material is also secured to the anglebracket 19 to guide the label tape over the bridge 18 and back towardthe surface of the plate 10 in advance of the separator edge 11. Theguide plate 20 is bifurcated toward its unsupported end affordingplacement of a label sensing device constructed in accordance with thepresent invention in the path of the label tape,

The label-sensing device of the present invention comprises a relativelynarrow axially supported hub 22 having outwardly extending tangentialteeth 23 defining a star wheel. The star wheel is mounted for rotationby a shaft 24. The shaft 24 is cantilever mounted from a bracket 25 andthe star wheel is bearinged on the shaft. Secured for rotation with thestar wheel is a cam 27 having generally planar surface portions 28joined by lobes 29, with a lobe to correspond with each tooth 23 on thehub 22. A leaf spring 30 supported from the bracket 25 has a free endpositioned in contact with the cam 27 tending to alternately restrictrotation of the star wheel and to urge rotation of the star wheel toatford control of the star wheel and permit its rotation only uponpositive contact of a tooth 23 thereof with the leading edge of thelabel 7 and to assure the position of a tooth 23 for contact with theleading edge of a subsequent label 7 upon each increment of rotation ofthe star wheel.

A switch 32 functions in response to the rotation of the star wheel andcam, from the position shown in FIG. 1 to the position of FIG. 3 andback to the position of FIG. 1, to carry out a control function. Theswitch 32 is supported in a position above the star wheel and has a camfollowing lever arm 33 disposed with a free end in contact with the cam27 such that upon the rotation of the star wheel and contact of the freeend of the arm 33 with a lobe 29 on the cam (see FIG. 3), a plunger 34of the switch 32 is actuated to open or close the contacts of the switchfor initiating a control function, e.g. the operation of the motordriving the flexible web.

The bridge 18 and its position above the planar label tape guidingsurface of the plate 10 defines an area along the path of the labeltape, where it is unsupported. This area allows the web to be flexed andallows the star wheel to rotate incrementally about the axis of itsshaft 24 against the bias of the spring 30 to operate the switch 32. Theangle bir 1-9, the bridge 18, and the label-sensing device asillustrated permit its location anywhere along the plate 10, affordingthe desired control for the web, with various sized labels.

Referring now to FIG. 4 there is illustrated an alternative form for thedispenser in the sensing device. In this embodiment the sensing devicecomprises a star wheel 35 and cam 36 but the plate 37, correspondinggenerally to plate 10, is provided with a recess 39 in the surfacethereof adjacent to the separating edge 38 and beneath the tape guide40. This recess 39 provides an unsupported area on the side of the labeltape opposite the sensing device permitting rotational movement of thestar wheel 35 much the same as the bridge 18.

The flexing of the web, i.e., the depression of the flexible web out ofits normal path into the recess 39 or below the bridge 18, affordspositive driving action for the star wheel to a greater extent thanafforded by the mere engagement of a tooth thereon with a label movingalong a linear path without deflection.

The present invention affords a sensing device which is positive andaccurate for the rapid control of the tape. It is a simplified devicecompared to the prior known devices and adaptable to existing equipment.

Having thus defined the present invention, What is claimed is:

1. A sensing apparatus for use with a flexible tape having articlesaflixed to one surface thereof in spaced relation, said apparatuscomprising a guide defining a path of movement for the flexible tape anddefining an area along said path where the tape is unsupported adjacentthe surface opposite the articles, a wheel mounted for rotation aboutits axis and having teeth extending outwardly from said wheel and intosaid path along which the flexible tape is guided, means for mountingsaid wheel for rotation about an axis fixed relative to said guide andopposite said area, cam means connected for rotation with said wheel,resilient means for restricting rotation of said Wheel except uponcontact of a tooth on said wheel with an article on a said tape movingalong said path, and means responsive to the incremental rotation ofsaid wheel and cam for carrying out a control function.

2. A label-applying apparatus comprising guide means defining a path fora flexible label-carrying tape leading to a transverse separating edge,said guide means defining at least one area in advance of the separatoredge where the label-carrying tape is unsupported, means for advancingthe label-carrying tape along said path over said one area and aboutsaid edge to separate the labels from the carrying tape, a star wheelpositioned on the side of said path opposite said one area of the tapepath and having circumferentially spaced teeth engageable with alabelcarrying tape and engageable with the lead edge of the labelsthereon to rotate the star wheel, means for supporting said star wheelfor rotation about an axis in fixed spaced relationship to said guidewhereby rotation of said star wheel will cause deflection of the tape atsaid unsupported area, a cam connected to said star wheel and rotatabletherewith, spring means engageable with said cam for restricting itsrotation and for positioning said star wheel upon rotation thereof, andmeans responsive to the incremental rotation of said star wheelaffording a control function.

3. A label-applying apparatus according to claim 2 wherein said meansaffording a control function comprises a switch having a plunger, alever arm engageable with said cam and operated thereby to move andplunger.

References Cited UNITED STATES PATENTS 3,039,516 6/1962 Vinal l56-3613,169,895 2/1965 Sohn l56-361 3,240,652 3/1966 La Mers 156-36l 3,405,02110/1968 Marano 156-361 3,447,992 6/1969 Allen et al 156-361 SAMUEL W.ENGLE, Primary Examiner D. A. BENT, Assistant Examiner US. Cl. X.R.156-541

